List filter & map performance comparision

README.md

Environment

• Node v8.1.2
• macOS 10.12.5
• MacBook Pro (Retina, 15-inch, Mid 2015)

Speed (faster come first)

Ramda > Lodash > reduce > filter > for

Conclusion

• It's good to learn funtional programming
  • for is the slowest.
  • The more functional, the faster
    • Ramda is faster than Lodash        - Note: this might not be ture, so I am just kidding. 😆
• It's good to use a mature library
  • Ramda & Lodash are the fastest.

index.js

const R = require('ramda')
const _ = require('lodash')

const getTimeInMillisenconds = () => {
  return (new Date).getTime();
}

const list = R.range(0, 10000000)
console.log(`THIS IS A DATA SET OF: ${list.length}`)

console.log('======filter=====')

let time = getTimeInMillisenconds()
let result = list.filter(i => i % 2 === 0)
console.log(`THIS IS THE RESULT: ${result.length}`)
console.log(`TIME SPENT: ${getTimeInMillisenconds() - time}ms`)

time = getTimeInMillisenconds()
result = list.filter(i => i % 2 === 0).map(i => i * 2)
console.log(`THIS IS THE RESULT: ${result.length}`)
console.log(`TIME SPENT: ${getTimeInMillisenconds() - time}ms`)

console.log()
console.log('=====reduce======')

time = getTimeInMillisenconds()
result = list.reduce((acc, item) => {
  if (item % 2 === 0) acc.push(item)
  return acc
}, [])
console.log(`THIS IS THE RESULT: ${result.length}`)
console.log(`TIME SPENT: ${getTimeInMillisenconds() - time}ms`)

time = getTimeInMillisenconds()
result = list.reduce((acc, item) => {
  if (item % 2 === 0) acc.push(item * 2)
  return acc
}, [])
console.log(`THIS IS THE RESULT: ${result.length}`)
console.log(`TIME SPENT: ${getTimeInMillisenconds() - time}ms`)

console.log()
console.log('=====Ramda=====')

time = getTimeInMillisenconds()
result = R.filter(i => i % 2 === 0, list)
console.log(`THIS IS THE RESULT: ${result.length}`)
console.log(`TIME SPENT: ${getTimeInMillisenconds() - time}ms`)

time = getTimeInMillisenconds()
result = R.map(i => i * 2, R.filter(i => i % 2 === 0, list))
console.log(`THIS IS THE RESULT: ${result.length}`)
console.log(`TIME SPENT: ${getTimeInMillisenconds() - time}ms`)


console.log()
console.log('=====for=====')

time = getTimeInMillisenconds()
result = []
for (const i in list) {
  if (i % 2 === 0) {
    result.push(i)
  }
}
console.log(`THIS IS THE RESULT: ${result.length}`)
console.log(`TIME SPENT: ${getTimeInMillisenconds() - time}ms`)

time = getTimeInMillisenconds()
result = []
for (const i in list) {
  if (i % 2 === 0) {
    result.push(i * 2)
  }
}
console.log(`THIS IS THE RESULT: ${result.length}`)
console.log(`TIME SPENT: ${getTimeInMillisenconds() - time}ms`)

console.log()
console.log('=====Lodash=====')

time = getTimeInMillisenconds()
result = _.filter(list, i => i % 2 === 0)
console.log(`THIS IS THE RESULT: ${result.length}`)
console.log(`TIME SPENT: ${getTimeInMillisenconds() - time}ms`)

time = getTimeInMillisenconds()
result = _.map(_.filter(list, i => i % 2 === 0), i => i * 2)
console.log(`THIS IS THE RESULT: ${result.length}`)
console.log(`TIME SPENT: ${getTimeInMillisenconds() - time}ms`)

result.txt

THIS IS A DATA SET OF: 10000000
======filter=====
THIS IS THE RESULT: 5000000
TIME SPENT: 895ms
THIS IS THE RESULT: 5000000
TIME SPENT: 1479ms

=====reduce======
THIS IS THE RESULT: 5000000
TIME SPENT: 358ms
THIS IS THE RESULT: 5000000
TIME SPENT: 362ms

=====Ramda=====
THIS IS THE RESULT: 5000000
TIME SPENT: 130ms
THIS IS THE RESULT: 5000000
TIME SPENT: 292ms

=====for=====
THIS IS THE RESULT: 5000000
TIME SPENT: 2254ms
THIS IS THE RESULT: 5000000
TIME SPENT: 2280ms

=====Lodash=====
THIS IS THE RESULT: 5000000
TIME SPENT: 235ms
THIS IS THE RESULT: 5000000
TIME SPENT: 275ms